Tube thickener



G. O. HlLLlER TUBE THICKENER Nov. 30, 1937.

Filed May 23, 1934 INVENTOR. GERALD 0. HILL/ER A TTORNEY Patented Nov. 30, 1937 UNITED STATES PATENT Fries mesne assignments,

to Oliver United Filters Incorporated, San Francisco, Calif., a corporation of Nevada Application May 23,

3 Claims.

This invention relates to tube thickeners.

Tube thickeners such as are now available on the market consist of a plurality of groups of cylindrical tubes, closed at both ends and the outer surfaces of which are covered with a filtering medium. The upper end of each tube is connected with an automatic valve by means of which each tube or each group of tubes may be subjected successively to the action of vaculun, and then to the action of a reverse pressure or blow. The tubes are submerged in a tank containing the slurry or pulp to be thickened. When the tubes are subjected to the action of a vacuum the solid content of the slurry or pulp is deposited as a cake on the outer surfaces of the tubes, while the clear filtrate passes into the interior of the tube, and then out through the automatic valve. When the pressure is reversed the filtrate contained in the piping between the automatic valve and the tube is forced back into the tube, displacing the filtrate contained within the tube, and dislodging the cake deposited on the outer surface of the tube. In practice several tubes are connected to a header by means of a union, and the header in turn communicates with the automatic valve. It frequently happens that one of these tubes has to be disconnected and taken out of the tank for purposes of inspection and repair. Ordinarily this is done while the tank is filled with slurry or pulp. To inspect a tube it must be disconnected from its header by means of the union above referred to. This of itself is time consuming. Since the entire tube is filled with filtrate it is relatively heavy and therefore awkward to handle. Furthermore, the tube contains a relatively large quantity of filtrate which must be drained before the tube can be inspected, entailing a further loss of time. After the tube has been inspected or repaired it must be replaced in the tank, and connected to the header. Since the tube is closed at both ends, and has a relatively large displacement, it has a correspondingly high buoyancy and therefore considerable diificulty is experienced in placing and holding the tube in a vertical position while it is being secured to its header.

In general the object of this invention is to overcome these difiiculties. V

More specifically one of the objects of the invention is the provision of a filtering tube having an open hollow core whereby the internal volumetric content of the tube is materially decreased and also its buoyancy.

Another object of the invention is the provision of a quickly detachable union between the tube 1934, Serial No. 727,101

and its header formed by means of a pair of complementary tapered fittings.

A still further object of the invention is the provision of a union between the tube and its header formed with a valve therein whereby upon 5 relative movement of the tube with respect to the header, communication between the tube and the header can be established or out 01f as desired.

A still further object of the invention is the provision of a conical guide member secured to 10 the lower portion of the thickener tank and by which its associated tube may be located in its proper position while the tube is being secured to its header.

The invention possesses other advantageous 15 features, some of which with the foregoing, will be set forth at length in the following description where that form of the invention which has been selected for illustration in the drawing accompanying and forming a part of the present 20 specification, is outlined in full. In said drawing, one form of the invention is shown, but it is to be understood that it is not limited to such form, since the invention as set forth in the claims may be embodied in a plurality of forms.

Referring to the drawing:

Figure 1 is a side elevation of a multiple tube thickener provided with an automatic valve, and in which the objects of my invention have been embodied.

Figure 2 is a side elevation with parts broken away showing the details of construction of the tubes used in the thickener as shown in Figure 1.

Figure 3 is a side elevation of the tapered joint or union by which a tube may be connected to its 35 associated header.

Figure 4 is an enlarged section taken on the line 44 of Figure 2.

Figure 5 is a side elevation partly in section of one of the conical guide members secured within 40 the lower portion of the thickener tank, and within which the lower end of its associated tube may be accommodated.

Figure 6 is a fragmentary plan view showing the method by which several tubes are connected to a single header.

As shown in Figure l the invention has been embodied in a thickener comprising a tank I, to the upper end of which has been secured a plurality of headers supported by means of brackets or beams 3. Conical guide members 4 are secured within the lower portion of the tank I by means of lugs 5, which are bolted or otherwise secured to the bracket or beam 6. Communicating with each header 2 is a plurality of filter tubes 1. In

actual practice four tubes are connected to each header as shown in Figure 6. Each header in turn communicates by means of a pipe 8 with an automatic valve 9, supported by the tank I. By means of this automatic valve, the details of construction of which are well known in the art, each group or cluster of tubes may be successively subjected first to the action of vacuum and then to the action of a reverse pressure or blow back.

As is customary in equipment of this type a scroll I l is provided in the lower portion of the tank for the purpose of moving the thickened sludge, pulp or slurry to the center of the tank where it is discharged through an outlet l2. Each filter tube, as shown in Figure 2, comprises an outer reticulated cylindrical shell l2, the outer surface of which is covered with a supporting screen 13. Disposed over the supporting screen I3 is a layer of any suitable filtering material 14, held in place by a wire winding I5. concentrically disposed within the reticulated shell l2 and slightly spaced therefrom is a second cylindrical shell IS. The cylindrical shells I2 and I6 define an annular filtrate compartment H, the lower end of which is closed by means of an annular plate I! welded or otherwise secured to the shells. The upper end of the filtrate compartment IT is similarly closed by means of an annular plate l9, which is provided with a central web 2|. Extending through a central bore in the web 2| and through the hollow core of the filter tube, is a filtrate pipe 22. This pipe 22 is secured to the web 2! by means of a collar 23, and communicates at its lower end with the filtrate compartment I! by means of an X 24. Depending from the X 24 is a stem 25 provided with a valve 26 by which the filtrate compartment l1 may be drained. The upper end of the filtrate pipe 22 terminates in a downwardly extending tapered fitting 27, adapted to be seated in a complementary tapered fitting 28 carried on the end of the header 2. The member 2'! has been shown as a male member in Figures 2 and 3, and the tapered fitting 28 as a female member. This relation however may obviously be reversed. From an inspection of Figure 2 it will be noted that the axis of the thrust bearing formed by the tapered fittings 21 and 28 is coincident with the axis of the filter tube. This construction is desirable in order that the tapered fitting 21 may properly seat within the tapered fitting 28.

Referring to Figure 3, it will be noted that the fitting 28 is provided with a port 29 in line with the header 2, and that the tapered fitting 2! is provided with a corresponding port 3| which may be placed in or out of registration with the port 29 upon the rotation of the filtrate pipe 22 and itsassociated tube. This construction therefore serves as a valve as well as a thrust bearing, and provides a convenient means by which any of the tubes of the thickener may be disconnected from the system at will.

The conical guide members 4 referred to in connection with Figure 1 are shown in greater detail in Figure 5. Each guide member 4 is provided with a lug 5 by means of which it may be secured as by bolts or rivets to the bracket or beam 6.

The advantages of this type of tube reside largely in the ease with which it may be removed from the system, and then after inspection or repair, installed in its proper position. The relatively low volumetric content of the filtrate compartment I'I materially decreases the quantity of filtrate contained within the tube, and therefore makes removal of the tube far easier. The low internal capacity of the tube also enables this type of tube to be drained within a far shorter period of time than the tubes now ordinarily used. The hollow central core of the tube materially decreases its buoyancy and therefore it may be submerged in the pulp or slurry and maintained in a vertical position with little or no trouble.

In order to guide the lower end of the tube to its proper position and to maintain it there while the connection is being made between the tapered fittings 2'! and 28 the stem 25 is inserted in the conical guide member 4.

It will be noted that communication between the filtrate pipe 22 and the filtrate compartment l! is made at the lower end of the filtrate compartment rather than at its upper end, as has been the practice in the past. This additional length of pipe serves a useful purpose inasmuch as it accommodates an additional quantity of filtrate which may be used together with the filtrate contained between the header 2 and the automatic valve 9 for the purpose of displacing the filtrate contained within the filtrate compartment H to thereby discharge or release the cake deposited on the outer surface of the filter medium [4.

I claim:

1. A thickener comprising a tank; a conical guide member supported within the lower part of the tank; a tapered fitting secured to the upper part of the tank, a tubular filtering element having a hollow core, a filtrate'pipe extending through said core and communicating with said filtering element, the upper end of said filtrate pipe being provided with a depending tapered fitting adapted to engage the tapered fitting secured to the upper part of the tank while the lower end of the filtrate pipe is adapted to be accommodated within said conical guide member.

2. A thickener comprising: a tank; a tapered fitting associated with the upper part of said tank; a filtering element vertically disposed witha,

in the tank; a filtrate pipe communicating at its, lower end with said filtering element and provided at its upper end with a goose neck terminating in a downwardly extending tapered fitting in engagement with said first mentioned tapered fitting; said tapered fittings being provided with ports adapted to be brought into and out of registration with each other upon the relative rotation of the fittings.

3. A thickener comprising: a tank; a tapered fitting secured to the upper part of the tank; a tubular filtering element having a hollow core; a filtrate pipe extending through said core and communicating with said filtering element; a depending tapered fitting secured to the upper end of said filtrate pipe and adapted to engage the tapered fitting secured to the upper part of the tank; a guide member secured to the lower end of said tank and a guide member secured to the lower end of said filtrate pipe, one of said members being in the form of an outwardly flaring female member while the other is in the form of a male member adapted to be received in said female member.

- GERALD O. HILLIER. 

